Cheat Sheet

Photovoltaic Design & Installation For Dummies

Sunlight allows photovoltaic (PV) modules (also called solar panels) to produce electricity and perform useful work, such as running electrical loads or putting energy back into the utility grid. To get started in the burgeoning business world of photovoltaic design and installation, you need to know a few basics, such as the main components in a PV system design, pointers for conducting site surveys, and safety guidelines to use during installation.

Major Components in a Photovoltaic System Design

New to photovoltaic (PV) systems (solar panels)? Haven't a clue what their major components are? Here's your chance to discover what goes into both grid-direct and battery-based PV system designs.

Following are the major components of a grid-direct system:

PV modules (which together form a PV array) with racking

A grid-direct inverter (listed to UL1741)

A combiner or junction box

A DC disconnect

An AC disconnect (possibly placed at the utility point of connection)

A meter to record the energy produced by the PV array

A utility interconnection across the circuit breaker inside the MDP

The major parts of a battery-based system include the following:

PV modules (which together form a PV array) with racking

A battery-based inverter (listed to UL1741)

A combiner box

A charge controller

A battery bank

Battery metering

DC overcurrent protection

An AC bypass switch and disconnects

DC disconnects

A main load center

A DC load panel located near the battery bank and DC disconnects (optional)

A generator (optional)

Designing Photovoltaic Systems: Site-Survey Tips

The best way to prepare to design a photovoltaic (PV) system is to conduct a site survey. This survey helps you get familiar with the client's property so you can better evaluate which location is best for housing the PV array. Here are some tips to make your site survey go smoothly:

Look at your client's site via satellite image before showing up in person so you can prepare for the site survey and even fill in some site information beforehand.

Bring a camera, a notepad with your standard site-survey form, pens and pencils, measuring tapes, and a shade-analysis tool so you can accurately document the site and define where to place the PV array.

Take more pictures and video than you think you need. You'll be glad you did when you're trying to remember a specific detail days or weeks after you were on-site.

Give yourself plenty of time — unless you're okay with missing an important detail just because you're in a hurry.

Staying Safe when Installing a Photovoltaic System

Installing a photovoltaic (PV) system often means you're working on a roof or other high place and definitely means electricity is involved. PV systems convert solar energy into electricity —and electricity is dangerous business. Following are pointers for staying safe when you install any kind of photovoltaic (PV) system:

Always assume the wires you're about to touch are live; make sure you're wearing proper personal protective equipment (PPE). At a minimum, your PPE should include safety glasses and high-voltage electrical gloves. It should also include a fall restraint if there's a chance you could fall more than 6 feet.

Never unplug a PV module connector without first measuring the current flow through the conductor with a digital multimeter.

Set up ladders at a 4-to-1 angle (a rise of 4 feet for a run of 1 foot) and with a minimum of three rungs above the roof line.

Start work early in the day and end early in the day. Installing PV systems places you in some extreme conditions, and even the most physically fit person will get worn down. No job is worth serious injury.

Installing PV systems is general construction work, which means the hazards associated with construction are applicable here. Get yourself trained in CPR and first aid, keep a first-aid kit on-site, and constantly communicate with others on-site to make everyone aware of any potential hazards.

Don't rush anything and always follow the instructions in the components' installation manuals.